1. Data Basics

2. Binary Number System Numeration systems are methods of representing numbers. All current number systems are positional in nature. In 34237 the two 3s represent different things because of their position: 30,000 and 30. People use the decimal system (probably because we have 10 fingers) which has 10 symbols, 0, 1, …, 9 Computers use the binary number system consisting of two digits, 0 and 1, because they can be implemented with switches being off or on. Switches are fast, reliable, and cheap.

3. Binary Numbers (continued) Binary numbers work just like decimal numbers (sort of) Decimal and binary represent the same values, just in different ways. Any whole number can be represented in either decimal or binary. Numbers can be converted from one system to the other. As users of computers we don’t need to do any of this, but it helps us understand some of the strange limitations that computers have. DO DEMO FOR CLASS.

4. Hexadecimal Number System Hexadecimal is a similar system that is often used by computer programmers and computer engineers. It is also used for conveying information such as MAC addresses. 00-1F-C6-80-13-AD is the MAC address of the computer in my office. Hex is just like binary and decimal (if we had 16 fingers) but it uses 16 symbols: 0, 1, … 9, A, B, …, F (a, b, … can be used in place of A, B, … MORE CLASS DEMOS.